Telescoping slide rail with latching and alignment mechanisms

ABSTRACT

A telescoping slide rail assembly including interconnected mounting, intermediate and stationary slide rails movable relative to one another to extend and retract the mounting and intermediate slide rails relative to the stationary slide rail between fully extended and retracted positions. The intermediate slide rail includes a latching mechanism for interconnecting the intermediate and stationary slide rails in the fully extended position and the mounting slide rail includes an alignment device to maintain orientation between the mounting slide rail and the intermediate slide rail.

[0001] This application claims priority under 35 U.S.C. §119(e) to U.S.Provisional Application Serial No. 60/438,586, filed Dec. 18, 2002,which is expressly incorporated by reference herein.

BACKGROUND OF THE INVENTION

[0002] This invention pertains to a telescoping slide rail assembly formounting components within a telecommunications rack, and moreparticularly, to a latching mechanism and alignment device used inconnection with the telescoping slide assembly for use in thetelecommunications industry.

[0003] There are numerous prior art telescoping slide rail devices formounting telecommunications equipment and other various components. Onemajor disadvantage of these prior art telescoping slide rail assembliesis that the latching mechanisms which orient and connect theintermediate slide rail to the stationary slide rail in a fully extendedposition are complex in design and relatively expensive to manufactureand install.

[0004] Another major disadvantage of these prior art telescoping sliderail assemblies is that manufacturing and assembly tolerances of theintermediate slide rail and the mounting slide rail are comparativelylarge and permit unwanted relative movement therebetween. As a result,there is a large tolerance variance between adjacent, parallel, offsetpairs of telescoping slide assemblies. Consequently, the mounting sliderail is loosely disposed within the intermediate slide rail. Unwantedmovement causes contact between the intermediate and mounting sliderails and friction therebetween is increased.

[0005] Therefore, there is a need for a latching mechanism which isinexpensive, easy to manufacture and install and simple and reliable tooperate. There is also a further need for an improved alignment devicewhich orients the slide rails, minimizes friction between the slidingrails and compensates for manufacturing tolerances.

BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The invention may best be understood by reference to thefollowing description taken in conjunction with the accompanyingdrawings, in the several figures of which like reference numeralsidentify like elements.

[0007]FIG. 1 is an exploded perspective view of a telescoping slide railassembly in accordance with one embodiment of the present invention.

[0008]FIG. 2 is an elevation view of the one side of a telescoping sliderail assembly of FIG. 1.

[0009]FIG. 3 is a cross-sectional view of the telescoping slide railassembly of FIG. 1 taken along line 3-3 in FIG. 2.

[0010]FIG. 4 is a cross-sectional view of the telescoping slide railassembly of FIG. 1 taken along line 4-4 in FIG. 2.

[0011]FIG. 5 is a cross-sectional view of the telescoping slide railassembly of FIG. 1 taken along line 5-5 in FIG. 2.

[0012]FIG. 6 is a detailed elevation view of the telescoping slide railassembly of FIG. 1 indicated as area 6 in FIG. 2.

[0013]FIG. 7 is a detailed elevation view of the telescoping slide railassembly of FIG. 6 illustrating a mounting slide rail just prior todisconnecting a latch mechanism.

[0014]FIG. 8 is a detailed elevation view of the telescoping slide railassembly of FIG. 7 illustrating the mounting slide rail disconnectingthe latch mechanism.

[0015]FIG. 9 is a detailed elevation view of the telescoping slide railassembly of FIG. 8 illustrating the latch mechanism disconnected.

[0016]FIG. 10 is an exploded detailed view of a roller including analignment device in accordance with one embodiment of the presentinvention.

[0017]FIG. 11 is a broken away detailed view of the roller and alignmentdevice of FIG. 10 as installed.

[0018]FIG. 12 is a broken away elevation view of a telescoping sliderail assembly in accordance with another embodiment of the presentinvention.

[0019]FIG. 13 is a cross-sectional view of the telescoping slide railassembly taken along line 13-13 in FIG. 12.

[0020]FIG. 14 is a broken away elevation view of the telescoping sliderail assembly of FIG. 12 illustrating a mounting slide rail disengaginga latch mechanism.

[0021]FIG. 15 is a cross-sectional view of the telescoping slide railassembly taken along line 15-15 in FIG. 14.

[0022] DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION

[0023]FIG. 1 is an exploded view of the improved telescoping slide railassembly of the present invention. Generally, the telescoping slide railassembly includes a stationary slide rail 12, intermediate slide rail 16and mounting slide rail 15.

[0024] The stationary slide rail 12, as will be described in more detailbelow, includes a wall 30, a top flange 32, a bottom flange 34, a toplip 36 and a bottom lip 38. A bracket may be connected to the wall 30adjacent an inner end 31 of the stationary slide rail 12 by fastenerswhich extend through holes 40 defined in the wall 30. Another bracketmay be connected to the wall 30 adjacent an outer end 29 of thestationary slide rail 12 by fasteners which extend through holes 40. Thebrackets are useful for mounting or connecting the stationary slide rail12 to a support. However, it will be recognized by one of skill in theart that the stationary slide rail may be mounted or connected to asupport with or without any brackets in any suitable manner.

[0025] The wall 30, upper flange 32 and upper lip 36 cooperativelydefine an upper channel 100. The wall 30, lower flange 34 and lower lip38 cooperatively define a lower channel 102. The upper and lowerchannels 100, 102 are configured to receive the intermediate slide rail16 in a nesting relationship for relative movement therebetween asdescribed herein. A retraction stop 104 is formed in the lower flange 34adjacent an inner end 31 of the stationary slide rail 12 for orientingthe intermediate slide rail 16 in a fully retracted orientation. A slot86 is defined in the lower lip 38 for operative engagement with aninterlock of the latch mechanism as described herein.

[0026] The intermediate slide rail 16, as will be described in moredetail below, includes one embodiment of a latch mechanism 50, includingan arm 22 which is connected at a mount portion to an inner end 17 ofthe intermediate slide rail 16 by a fastener 52. An interlock 23 isconnected to a free end 25 of the arm 22 by a fastener 3. A stop pivot24 is connected to the intermediate slide rail 16 for operative contactwith the arm 22 in order to enable disconnection of the intermediateslide rail 16 and stationary slide rail 12, as will be discussed in moredetail herein. A slide block 21 is connected to the intermediate sliderail 16 adjacent an inner end 17 for reducing friction between theintermediate and stationary slide rail 16, 12 during relative movement.It is within the teachings of the present invention that the arm 22 maybe formed from a material suitable for the arm 22 to function as abiasing element. For example, the arm 22 may be formed from anyresilient metallic, plastic, natural, synthetic or other suitablematerial which permits the arm 22 to function to not only position andorient the interlock, but also as a biasing element.

[0027] The intermediate slide rail 16 includes a back 90, an upperelement 106 and a lower element 108. The wall 90 and upper element 106cooperatively define an upper guide 110. The wall 90 and the lowerelement 108 cooperatively define a lower guide 112. The upper and lowerguides 10, 112, engage the mounting slide rail 15 in a nestingrelationship as shown in FIG. 4. The lower element 108 has an innerflange 192 disposed to engage the interlock as will be discussed below.

[0028] The inner end 17 of the intermediate slide rail 16 is illustratedin detail in FIGS. 6-9. A flange 114 is formed at the inner end 17 toprovide a mounting point for the latch mechanism 50. A stop pivot 24 isconnected to the intermediate slide rail 16 in any suitable conventionalmanner. A tab 94 is formed adjacent the stop pivot 24 to confine aportion of the arm 22 between the tab 94 and the stop pivot 24. A tab116 is defined on the intermediate slide rail 16 adjacent the flange 114for engaging the slide block 21 in order to orient the slide block 21 inoperation. An extension stop 118 is formed in the wall 90 of theintermediate slide rail 16 adjacent the outer end 81 for operativelyengaging the mounting slide rail 15 as discussed herein. A slot 120 isdefined in the upper element 106 for a passageway to facilitate acomponent (not shown) to engage the mounting slots 70, as described inmore detail in U.S. patent application Ser. No. 10/318,850, incorporatedfully herein.

[0029] The mounting slide rail 15, as will be discussed in more detailbelow, includes a wall 60, a top flange 62, a bottom flange 64, a toplip 66 and a bottom lip 68. A plurality of slots 70 are defined in thetop flange 62 and wall 60 which preferably, operatively engage mountingposts disposed on a component for mounting hereto. Another bracket maybe connected to an inner end 113 of the mounting slide rail 15 viafasteners which engage holes 72.

[0030] A pair of rollers 13 are connected to the wall 60 by hubs 14which engage holes 74 in a conventional manner which may include a pressfit, fastener or other suitable mechanical connection including bonding,welding, adhering or in any other suitable manner. A bearing 11 isdisposed within the free end enlarged head element of the hub 14, aswill be discussed in more detail herein. Preferably, the bearing 11 isretained within the hub 14. It is within the teachings of the presentinvention that the bearing may be in ball bearing, fixed bearing or anyother suitable bearing element. It will be recognized by those of skillin the art that the bearing may be configured in any suitable shape andfrom any suitable material such as any metallic, plastic, synthetic,composite or any other suitable material.

[0031] A mounting post engaging latch 18 is connected to the wall 60 andbiased into position by spring 19. A mounting slide rail retraction stop20 is connected to the wall 60 by fastener 17. A spring may be providedto bias the retraction stop 20 into a position to engage the outer end89 of the intermediate slide rail 16.

[0032] A notch 140 is formed in the lower flange and lip 64, 68 toprovide clearance for the roller 13 secured to hole 74. A tab 144 isformed in the lower lip and flange 68, 64 and the wall 60 for engagingthe extension stop 118 formed on the intermediate slide rail 16 in orderto prevent the mounting slide rail 15 from disconnection with theintermediate slide rail 16. A tongue 146 is defined at the inner end 143of the mounting slide rail 15. The tongue 146 has a tab 148 formed atthe distal end thereof for engaging a bearing portion of the arm 22 ofthe latch mechanism 50 to enable disengagement of the intermediate sliderail 16 from the stationary slide rail 12 for retraction of theintermediate slide rail 16, as will be described in detail herein.

[0033]FIG. 2 illustrates an elevation view of one embodiment of thetelescoping slide rail assembly of the present invention assembled anddisposed in a fully extended orientation. A flange 80 of the retractionstop 20 extends through a slot 82 formed in the mounting slide rail 15to engage an outer end 84 of the intermediate slide rail 16 to preventunintended retraction of the mounting slide rail 15. Movement of theretraction stop handle against the spring bias moves the flange 80 toanother operative position out of engagement with the outer end 84 inorder to enable retraction of the mounting slide rail 15 within theintermediate slide rail 16.

[0034] The interlock 23 of the latch mechanism 50 engages a firstopening 86 formed in the lip 38 of the stationary slide rail 12 to lockthe intermediate slide rail 16 in a fully extended position with respectto the stationary slide rail 12. The retraction stop 20 and mountingpost engaging latch 18 are connected to the mounting slide rail 15 suchthat each respective handle is available for operative movement by auser when the mounting slide rail is disposed in the fully extendedposition as is described in more detail in U.S. patent application Ser.No. 10/318,850 incorporated fully herein.

[0035]FIG. 3 is a cross-sectional view taken along line 3-3 in FIG. 2,which illustrates the stationary slide rail 12 and the intermediateslide rail 16 disposed in a nesting relationship.

[0036]FIG. 4 is a cross-sectional view taken along line 4-4 in FIG. 2,which illustrates the mounting slide rail 15 in a nesting relationshipwith intermediate slide rail 16, which is in a nesting relationship withthe stationary slide rail 12. Roller 13 is connected to the mountingslide rail 15 by a hub 14. A bearing 11 is disposed in an enlarged headelement 154 free end of the hub 14. Bearing 11 is disposed such that aportion is immediately adjacent an inner surface of wall 90 of theintermediate slide rail 16 so that minimal lateral movement in thedirections of arrow 92 is permitted.

[0037]FIGS. 10 and 11 illustrate the improved roller and hub 13, 14 ofthe present invention. The hub 14 includes a mounting element 150, asupport element 152, an enlarged head element 154 and a receptacle 156.The mounting element 150 engages one of the holes 74 (see FIG. 1) toconnect the roller 13 to the mounting slide rail 15. The support element152 supports the roller 13 for relative rotational movement when themounting slide rail 15 is moved relative to the intermediate slide rail16. The enlarged head element 154 retains the roller 13 connected to themounting slide rail and to a certain degree prevents unwanted lateralmovement of the roller 13 in the direction of arrow 92 with respect tothe mounting slide rail 15. The receptacle 156 is configured to receiveand retain the bearing 11.

[0038] The roller 13 includes an opening 160 which is configured toreceive the hub 14. A first portion 162 of the opening 160 is configuredto receive the enlarged head element 154. A recessed face 164 is formedin the roller 13 to reduce rolling friction with respect to an adjacentwall of the intermediate slide rail 16.

[0039]FIG. 5 is a cross-sectional view taken along line 5-5 in FIG. 2,which shows one embodiment of the latch mechanism 50 including theinterlock 23 disposed within the first opening 86 formed in thestationary slide rail 12. Stop pivot 24 and tab 94 cooperatively retainthe arm 22 therebetween and confine movement of the arm 22 duringrelease of the interlock 23 from the first opening 86 as will bediscussed in detail below. The slide block 21 is connected to an uppertab portion 116 of the intermediate slide rail 16 and functions tostabilize the intermediate slide rail 16 at the inner end 17 thereof andto reduce friction between the intermediate and stationary slide rails16, 12.

[0040]FIGS. 6-9 illustrate the structural and functional aspects of oneembodiment of the latch mechanism 50 of the present invention. The arm22 is preferably configured from spring steel. However, it is within theteachings of the present invention that any suitable resilient materialmay be substituted therefor. For example, any resilient synthetic ornatural material, plastic or any other suitable resilient material maybe used. Arm 22 includes a main element 124 having a bearing portion 123defined thereon and a pair of mirror image opposed ends 26, 28. A holeis formed in each of the ends 26, 28 for engaging a fastener 52, 3 toconnect the arm 22 to the flange 114 at the mount portion of theinterlock 23. One advantage of the present invention is that it isirrelevant which opposing end 26, 28 is attached to the flange 114 orthe interlock 23. As a result, manufacture and installation are greatlysimplified.

[0041] The stop pivot 24 includes a mounting portion, a bearing portion(134, see FIG. 5) and an enlarged head portion 136. The main element 124of the arm 22 contacts the bearing portion 134 when the arm 22 isdeflected as a result of contact between an inner end 143 of themounting slide rail 15 and the bearing portion 123 of the main element124, as will be discussed in detail herein. The stop pivot mountingportion engages a hole defined in the intermediate slide rail 16 forconnection thereto in a conventional manner.

[0042] The interlock 23, in one embodiment of the present invention, isgenerally configured as a block for engaging the first opening 86 formedin the stationary slide rail 12, the lower lip 38 and the inner flange192, which defines a second opening 87, to prevent relative movementbetween the intermediate and stationary slide rails 16, 12. The firstopening 86 and inner flange 192, which defines the second opening 87,cooperatively engage opposing sides of the interlock 23 in order toprevent retracting movement of the intermediate slide rail 16 from thefully extended position. It is within the teachings of the presentinvention that the interlock 23 may be configured in a suitable shape toprovide the intended function and from any suitable material for anintended application.

[0043]FIGS. 12-15 illustrate the structural and functional aspects ofanother embodiment of the latch mechanism 50 of the present invention.The arm 22 is preferably configured from a metallic material. However,it is within the teachings of the present invention that any suitablemetallic, plastic, synthetic or natural material may be used.

[0044] Arm 22 includes a mount portion 150 and an interlock 23 and aflange 152 defining a bearing portion 123, both extending from the mountportion 150. In this embodiment of the present invention the mountportion 150 is configured generally tubular such that a pin 156 passingtherethrough along a longitudinal axis or engaging openings at oppositeends of the mount portion 150 aligned on the longitudinal axis enablesthe mount portion 150 to move about the pin 156. The arm 22 may alsothen be connected to the intermediate slide rail 16.

[0045] The interlock 23 in this embodiment of the present invention isgenerally configured as a hooked finger 158 extending away from themount portion 150 in the direction of the mounting slide rail 15. Theinterlock 23 preferably bends back generally toward the mount portion150 and in the direction of the wall of the intermediate slide rail 16to form the “hooked” portion at the distal end. It is within theteachings of the present invention that the interlock may take anysuitable form or configuration to secure the intermediate and stationeryslide rails as described in more detail below.

[0046] The flange 152 extends away from the mount portion 150 generallynormal to the intermediate slide rail 16 when the intermediate sliderail is disposed in a fully extended position, as shown in FIGS. 12 and13. A front face of the flange 152 defines the bearing portion 123 whichis disposed and oriented for contact by the tongue 146 as shown in FIGS.14 and 15 and as will be described in more detail below.

[0047] A biasing element 160 in this embodiment of the present inventionis generally configured as a coil spring bearing against a side of theflange 152 opposite the bearing portion 123 at one end 162 and againstthe intermediate slide rail 16 at another end 164. It is within theteachings of the present invention that any other suitable type ofbiasing element may be used. For example, flat springs, contour springelement and any other suitable biasing device may be used. As shown inFIGS. 12 and 13, the spring 160 biases the flange 152 in the directionof the mounting slide rail 15 such that the arm 22 rotates about themount portion 150. As a result, the interlock 23 is continuously biasedin the direction of the wall 90 of the intermediate slide rail 16.

[0048] The latch mechanism 50 further includes a first opening 86 formedin the wall 30 of the stationary slide rail 12 and a second opening 87formed in the wall of the intermediate slide rail 16. The first andsecond openings 86, 87 are aligned when the intermediate slide rail 16is disposed in a fully extended position. The interlock 23 may thenengage the aligned openings 86, 87 and prevent unwanted movement of theintermediate slide rail 16 toward the fully retracted position. Thespring 160 biases the arm 22 such that after disengagement of theinterlock 23 from the first opening 86 and movement of the intermediateslide rail 16 toward a fully retracted position, the hooked finger 158extends through the second opening 87 in a non-operative positionsliding against the wall 30 of the stationary slide rail 12.

[0049] In operation, the telescoping slide assembly of the presentinvention when disposed in a fully retracted position may be moved to afully extended position (see FIG. 2) for servicing or installing acomponent which may be connected to the mounting slide rail 15 asdiscussed in U.S. patent application Ser. No. 10/318,850 incorporatedfully herein. In this process, an operator grasps the component or outerend 141 of the mounting slide rail 15 and pulls outwardly away from thesupport to which the telescoping slide assembly is connected, generallyin the direction of arrow 300, shown in FIG. 2. The intermediate sliderail 16 also moves from a fully retracted position to a fully extendedposition relative to the stationary slide rail 12 which does not moverelative to the support. In one embodiment of the present invention, theintermediate slide rail 16 remains in a fully retracted position, untilthe mounting slide rail 15 extends to the fully extended position. Inanother embodiment of the present invention, the mounting andintermediate slide rails 15, 16 move together as a unit from a fullyretracted position. In such embodiment, the mounting slide rail 15remains in a fully retracted position with respect to the intermediateslide rail 16 until the intermediate slide rail 16 is disposed in afully extended position. At such time, the mounting slide rail 15 isthen moved to its fully extended position.

[0050] Further discussion of the operation of the telescoping slide railassembly of the present invention will be with reference to the firstembodiment described above. However, it will be recognized by those ofskill in the art that the second embodiment described above operates inthe same manner, except as noted above.

[0051] In one embodiment of the present invention, when the intermediateand mounting slide rails 16, 15 are disposed in a fully retractedposition, the mounting slide rail 15 may be extended from the fullyretracted position to the fully extended position. The latchingmechanism 50, particularly the interlock 23, is disposed in anon-operative position, either above the lower lip 38 or sliding againstthe wall of the stationary slide rail, and remains unassociated with thefirst opening 86. The mounting slide rail 15 is moved further outward inthe direction of arrow 300 until disposed in a fully extended positionwhere the flange 80 of retraction stop 20 engages slot 82 and outer end84. The intermediate slide rail 16 is then also moved to a fullyextended position where the interlock 23 engages the first opening 86 asshown in FIGS. 6, 12 and 13.

[0052]FIGS. 6, 12 and 13 illustrate the intermediate slide rail 16disposed in the fully extended position with respect to the stationaryslide rail 12. The interlock 23 engages the first opening 86 and thesecond opening 87 (defined by the inner flange 192 in one embodiment) tolock or secure the intermediate and stationary slide rails 16, 12together. When an operator desires to retract the telescoping slide railassembly of these embodiments of the present invention, such that themounting slide rail 15 is retracted into the intermediate slide rail 16,the retraction stop 20 is disengaged so that the mounting slide rail 15moves opposite arrow 300 (see FIG. 2) relative to the intermediate sliderail 16. When the mounting slide rail 15 is disposed nearly at the fullyretracted position, the tongue 146 will contact the bearing portion 123of the arm 22 to disengage the latch mechanism 50 from the first opening86 and stationary slide rail 12.

[0053]FIG. 7 illustrates the intermediate slide rail 16 disposed in afully extended position. The mounting slide rail 15 has been moved fromthe fully extended position after release of the retraction stop 20. Thefree end of the tongue 146 has moved into contact with the bearingportion 123 of the main element 124 on the arm 22.

[0054]FIGS. 8, 14 and 15 illustrate the further movement of the mountingslide rail 15 with respect to intermediate slide rail 16. The mountingslide rail 15 has been moved inwardly, opposite arrow 300 (see FIG. 2),such that the free end of the tongue 146 contacts the bearing portion123 of the arm 22. In FIG. 8, the tongue 146 moves the bearing portion123 of the main element 124 into contact with the bearing portion 134 ofthe stop pivot 24. Because the end of the arm 22 opposite the interlock23 is fixed and the free end of the tongue 146 contacts the bearingportion 123 of the main element 124 between the end fixed at the mountportion and the stop pivot 24, the arm 22 bends such that the interlock23 moves out of engagement with the first opening 86 and the innerflange 192, i.e. second opening 87. As a result, the intermediate sliderail 16 may then be moved from the fully extended position to the fullyretracted position.

[0055] In FIGS. 14 and 15, the tongue 146 contacts the bearing portion123 and moves the flange 152 such that the mount portion 150 rotatesabout the pin 156 against the bias of spring 160 so that the interlock23 disengages the first opening 86. As a result, the intermediate sliderail 16 may then be moved from the fully extended position to the fullyretracted position. One particular advantage of this embodiment is arobust engagement of the first opening which does not fail. Anotheradvantage is exceptional operational reliability.

[0056]FIG. 9 illustrates the intermediate slide rail 16 moved from thefully extended position relative to the stationary slide rail 12. Theinterlock 23 has been moved out of engagement with the first opening 86to permit movement of the intermediate slide rail 16 to the fullyretracted position. The arm 22 remains bowed and the main element 124remains in contact with stop pivot 24 such that the interlock 23 isdisposed above the lower lip 38.

[0057] It will be recognized by those of skill in the art that theelement identifiers “stationary”, “intermediate” and “mounting”, whenused in connection with the slide rails, merely serve to identify thedifferent rails rather than strictly defining any of their functions.Other element identifiers may have been first, second and third sliderails. However, those element identifiers were not used in order toeliminate confusion and mistakes in understanding the present invention.

[0058] Although the invention has been described in detail withreference to certain preferred embodiments, variations and modificationsexist within the scope and spirit of the invention as described anddefined in the following claims. For example, the latch arm andinterlock may be formed from a single element and use fewer fasteners.

What is claimed is:
 1. A telescoping slide rail assembly comprising: astationary slide rail and an intermediate slide rail interconnected suchthat the intermediate slide rail is movable relative to the stationaryslide rail to extend and retract between a fully extended position and afully retracted position; the intermediate slide rail including a latchmechanism that engages a first opening in the stationary slide rail whenthe intermediate slide rail is disposed in the fully extended positionin order to secure the intermediate slide rail in the fully extendedposition until the latch mechanism is disengaged; and the latchmechanism including an second opening formed in the intermediate sliderail, an arm having a bearing portion and an interlock and a biasingelement configured and disposed such that the interlock engages thefirst and second openings, when aligned, and prevents unwanted movementof the intermediate slide rail toward the fully retracted position. 2.The telescoping slide rail assembly as recited in claim 1, furtherincluding a mounting slide rail interconnected to the intermediate sliderail for movement relative thereto such that the mounting slide railextends and retracts relative to the intermediate slide rail between afully extended position and a fully retracted position.
 3. Thetelescoping slide rail assembly as recited in claim 2, wherein themounting slide rail includes a tongue disposed at an inner end of themounting slide rail for engaging the latch arm in order to disengage thelatch mechanism.
 4. The telescoping slide rail assembly as recited inclaim 3, wherein the tongue contacts the bearing portion to disengagethe latch mechanism.
 5. The telescoping slide rail assembly as recitedin claim 4, wherein the arm has a mount portion connected to theintermediate slide rail and a free end having the interlock disposedthereon such that the bearing portion is disposed between the mountportion and the free end.
 6. The telescoping slide rail assembly asrecited in claim 4, wherein the arm has a mount portion connected to theintermediate slide rail, a free end having the interlock disposedthereon extending from one side of the mount portion and a flangedefining the bearing portion extending from another side of the mountportion.
 7. The telescoping slide rail assembly as recited in claim 5,wherein the intermediate slide rail further includes a stop pivotdisposed adjacent the arm such that the arm engages the stop pivotfollowing contact by the tongue when the mounting slide rail is moved toa fully retracted position.
 8. The telescoping slide rail assembly asrecited in claim 7, wherein the stop pivot is disposed closer to thefree end than to the mount portion.
 9. The telescoping slide railassembly as recited in claim 7, wherein the tongue contacts the armbetween the stop pivot and the mount portion, deflecting the arm suchthat the interlock may be disengaged from the aligned first and secondopenings when the mounting rail is disposed in the fully retractedposition.
 10. The telescoping slide rail assembly as recited in claim 7,wherein the intermediate slide rail includes a tab disposed adjacent thearm opposite the stop pivot such that the arm is disposed therebetween.11. The telescoping slide rail assembly as recited in claim 1, whereinthe intermediate slide rail includes a lower element having an innerflange, which defines the second opening, disposed to engage theinterlock to prevent movement of the intermediate slide rail toward thefully retracted position.
 12. The telescoping slide rail assembly asrecited in claim 11, wherein the inner flange and first openingcooperatively engage opposing sides of the interlock in order to preventmovement of the intermediate slide rail from the fully extendedposition.
 13. The telescoping slide rail assembly as recited in claim 1,wherein the intermediate slide rail includes a glide block disposed toreduce friction between the stationary and intermediate slide rails. 14.The telescoping slide rail assembly as recited in claim 7, wherein thestop pivot includes an enlarged head portion to maintain the arm in analigned orientation.
 15. The telescoping slide rail assembly as recitedin claim 1, wherein the latch mechanism is configured as an integralelement.
 16. The telescoping slide rail assembly as recited in claim 2,wherein the mounting slide rail includes at least one alignment device.17. The telescoping slide rail assembly as recited in claim 3, whereinthe tongue includes a tab disposed at a free end thereof which engagesthe arm.
 18. The telescoping slide rail assembly as recited in claim 1,wherein the biasing element is formed from a desired material so thatthe arm may function as the biasing element.
 19. The telescoping sliderail assembly as recited in claim 6, wherein the tongue contacts thebearing portion to pivot the arm about the mount portion so that theinterlock disengages the first opening whereby the intermediate sliderail may be moved toward a fully retracted position.
 20. The telescopingslide rail assembly as recited in claim 6, wherein the interlock isconfigured as a hooked finger which passes through the first opening tocontact a wall of the stationary slide rail.
 21. The telescoping sliderail assembly as recited in claim 6, wherein the biasing element is acoil spring bearing against the flange at one end and against theintermediate slide rail at another end.
 22. A telescoping slide railassembly comprising: an intermediate slide rail and a mounting sliderail interconnected such that each is movable relative to the other sothat the mounting slide rail extends and retracts between an extendedposition and a retracted position; the mounting slide rail including analignment device including a hub connected to the mounting slide railfor rotatably supporting a roller; the hub configured to operativelysupport a bearing to maintain alignment of the mounting slide rail withrespect to the intermediate slide rail.
 23. The telescoping slide railassembly as recited in claim 22, wherein the alignment device includes apair of hubs each connected to the mounting slide rail for rotatablysupporting a roller and disposed at spaced positions.
 24. Thetelescoping slide rail assembly as recited in claim 23, wherein one hubis disposed adjacent an inner end of the mounting slide rail and anotherhub is disposed between the inner end and an outer end of the mountingslide rail.
 25. The telescoping slide rail assembly as recited in claim22, wherein the hub includes a receptacle formed in an enlarged headelement for operatively supporting the bearing.
 26. The telescopingslide rail assembly as recited in claim 22, wherein the bearing isconfigured as generally spherical.
 27. The telescoping slide railassembly as recited in claim 22, wherein the hub is connected to a wallof the mounting slide rail and the bearing operatively engages a wall ofthe intermediate slide rail so that top and bottom lips of the mountingslide rail and the roller remain correctly disposed within upper andlower guides of the intermediate slide rail in order to reduce friction.28. The telescoping slide rail assembly as recited in claim 22, whereinthe roller includes a recessed face to reduce rolling friction withrespect to the intermediate slide rail.